We knew the upgraded S63tu (technical update) Twin Turbo 4.4 liter V8 in the F10 M5 would be stronger than the standard S63 Twin Turbo V8 4.4 liter units in the X5M and X6M even accusing BMW of sandbagging. We just did not think it would be this much stronger. We first reported on the differences between the S63 V8's in the M SUV's and the F10 M5 in June of last year and the M5 S63tu V8 has higher compression at 10.0:1 versus 9.3:1 and runs more boost at 22 psi versus 17 psi for the SUV's.

Well, the end result is 527 rear wheel horsepower completely stock on pump gas. This dyno comes to us courtesy of our Premier Vendor IND-Distribution whom we thank for sharing it with us.

To put this power in perspective, the X5M and X6M put down 456 all wheel horsepower stock on 93 octane in SAE on a dynojet. So the M5 is much, much stronger partially due to routing the power to the rear wheels with a dual clutch transmission versus all four with an automatic and also due to more boost with higher compression.

For those who like to calculate drivetrain losses, the M5 is rated at 560 horsepower stock. That would put the drivetrain losses at 6%. Using the traditional dynojet standard of 15% the rear wheel horsepower should be at 476. BMW is underrating the new turbo motors and especially the M motors considerably. We are definitely glad they are over-delivering.

Well, the end result is 527 rear wheel horsepower completely stock on pump gas. This dyno comes to us courtesy of our Premier Vendor IND-Distribution whom we thank for sharing it with us.

Nice to see a dyno of the new M5. I was thinking all along that this engine had to be underrated by BMW. While everyone has been raving over how fast the the new Shelby GT500 is (myself included), this latest M5 has been right on the Shelby's heels in acceleration, be it 0-60, the quarter mile, or terminal speed at the end of the quarter...and doing that while having a 300-400 pound weight penalty over the Shelby. Knowing it puts a bit over 500 to the wheels certainly explains how this car runs like a scalded cat and can almost keep up with the GT500 in an acceleration run.

Seriously, these numbers are ridiculous. This car is a true beast. It will be interesting to see where the tunes head not only for the M5, but the 550 as well. The best part is it's not just hp, but torque too.

Although I wouldn't call the new M5's engine "high revving" (in comparison to other M engines) but it sure is amazing that it's making more power than the Merc is at its redline - and then continues on for another 1000 RPMs... Wow.

I have a feeling we will see some impressive things with this engine in regard to tuning.

Although I wouldn't call the new M5's engine "high revving" (in comparison to other M engines) but it sure is amazing that it's making more power than the Merc is at its redline - and then continues on for another 1000 RPMs... Wow.

I have a feeling we will see some impressive things with this engine in regard to tuning.

Underrated is right - 6% DTL - LOL.

Cheers.

The M5 turbo setup is more efficient than the M157 and the twin scroll setup will get more HP with the extra exhaust pulses. I have an article explaining it if you want to read about it.

Seriously, these numbers are ridiculous. This car is a true beast. It will be interesting to see where the tunes head not only for the M5, but the 550 as well. The best part is it's not just hp, but torque too.

I'm concerned this motor won't have too much room to play, looks BMW went pretty aggressive to make a point. Message received.

I was thinking about getting away from BMW but an F13 M6 convertible might be a nice ride to pick up...

The M6 is going to be bad ass! It might be heavy but it has $#@! ton of power. Drove through the dealership a couple of weeks ago an they had a couple of regular 6 series. Beautiful cars and I think they looked small compared to pics. I will tell what sucks though....the.curved down front end of the new 3...looks dumb as $#@!...they also had a 6 series grand coupe, anyone that pays the premium for that over a 5 series is a $#@!ing dumbass.